Duolingo maintains excellence as the default standard by hiring exceptional talent and rejecting the 'minimum viable product' mindset.The company emphasizes moving fast but letting data lead decision-making, ensuring speed with rigor in scaling what actually works.Engagement through delight is key for Duolingo, with playful branding and gamification boosting retention and passion in teams.Duolingo's blend of mission, rigor, and whimsy offers a blueprint for sustainable growth, aligning decisions with long-term vision and user trust.